1. Field of the Invention
The present invention relates to a board installation member used to install a circuit board and to a receiving apparatus comprising the board installation member.
2. Description of the Related Art
Conventionally, for example, as a receiving apparatus that receives broadcast waves, a receiving apparatus that has a circuit board installed on a metal chassis has been used. A structure of such a receiving apparatus is explained below referring to FIG. 8.
As shown in this figure, a receiving apparatus includes a tuner portion 101 and a main body portion 102 both of which are provided with a circuit board, and installed on a main board 109. The tuner portion 101 and the main body portion 102 are covered with metal chassis 114 and 126, respectively.
The tuner portion 101 comprises a tuner input terminal 111, a tuner circuit portion 112, and an output terminal 113 for an intermediate-frequency signal, while the main body portion 102 comprises input terminals 121 for an intermediate-frequency signal, a first circuit portion 122, a second circuit portion 123, a third circuit portion 124, and image apparatus connecting terminals 125.
In the structure described above, the receiving apparatus receives a digital broadcast wave and inputs broadcast signals into the tuner circuit portion 112 via the tuner input terminal 111. The tuner circuit portion 112 extracts (selects) a predetermined-frequency signal form the broadcast signals, converts it into an intermediate-frequency signal, and outputs it to the main body portion 102 via the output terminal 113.
The main body portion 102 receives the intermediate-frequency signal via the input terminals 121 and transmits it to the first circuit portion 122. The first circuit portion 122 demodulates the received signal and outputs it to the second circuit portion 123. The second circuit portion 123 decompresses the received signal and outputs it to the third circuit portion 124.
The third circuit portion 124 converts the original digital image and sound signals obtained by the decompression processing into analog image and sound signals. And the analog image and sound signals are output to an image apparatus, not shown, and the like via the image apparatus connecting terminals 125.
The chassis (114, 126) which cover the tuner portion 101 and the main body portion 102 are installed on the main board 109 so that the tuner portion 101 and the main body portion 102 are fixed to the main board 109. The chassis (114, 126) are each provided with a protrusion that supports a circuit board fixed inside so that the circuit board is prevented from coming off. The input terminals 121 for intermediate-frequency signals and the image apparatus connecting terminals 125 are installed on the chassis 126. As documents on the prior art, there are JP-A-2000-68673, and JP-A-1999-341375.
In the receiving apparatus described above, when installing the circuit board of the main body portion 102 on the main board 109, the chassis 126 covering the main body portion 102 is used. Accordingly, the chassis 126 is indispensable for the main body portion 102, and it is hard to reduce the size of the main body portion 102. Thus, size reduction of the receiving apparatus is impeded. Besides, because the input terminals 121 and the image apparatus connecting terminals 125 are disposed outside the chassis 126, it is all the more difficult to achieve the size reduction.
In addition, because it is necessary to install the input terminals 121 and the image apparatus connecting terminals 125 on the chassis 126 in advance and to dispose a protrusion and the like to support the circuit board. Therefore, the structure and the fabrication method of the chassis 126 become relatively complicated, which is a factor to impede price reduction of the product.